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## Main Question or Discussion Point

I'm working my way through

Consider a carbon-carbon double bond: C=C. He says that there are a few different ways that the pi electrons can be distributed in this bond:

C=C

(-)C--C(+)

(+)C--C(-)

.C--C.

Where the last structure is a radical. Although some of those structures are theoretically possible, they would offer a poor description of the behavior of the C=C . So, he develops a set of rules for which theoretical contributing structures are higher in energy and thus poorer descriptions of the chemical behavior.

So my question is, is this definition of "higher energy" a literal definition? Or am I misunderstanding the definition of resonance: degenerate solutions for the energy term in the Schrodinger equation--i.e., of equal energy!

*The Art of Writing Reasonable Organic Reaction Mechanisms*by Robert B. Grossman (excellent book, by the way), but the way he describes resonance is confusing me. I feel like the more I think about it, the more confusing it gets.Consider a carbon-carbon double bond: C=C. He says that there are a few different ways that the pi electrons can be distributed in this bond:

C=C

(-)C--C(+)

(+)C--C(-)

.C--C.

Where the last structure is a radical. Although some of those structures are theoretically possible, they would offer a poor description of the behavior of the C=C . So, he develops a set of rules for which theoretical contributing structures are higher in energy and thus poorer descriptions of the chemical behavior.

So my question is, is this definition of "higher energy" a literal definition? Or am I misunderstanding the definition of resonance: degenerate solutions for the energy term in the Schrodinger equation--i.e., of equal energy!